Plant stem defense—spines
This article will discuss the defense mechanisms of plant stems—spines and plants with thorny stems. Over millions of years of evolution, plants have developed many self-protection abilities, with many plants growing spines on various parts to resist the invasion of herbivores.
Herbivores rely on plants for survival, but plants also protect themselves. Plants can grow branch spines, leaf spines, and skin spines on their stems, which can at least deter some herbivores.
Branch spines develop from the stems and contain vascular tissue. The entire spine can branch out, and some branch spines even have their own leaves. They are usually hard and lignified.
Leaf spines, like branch spines, contain vascular tissue, but leaf spines originate from leaves or specific parts of leaves, such as stipules or petioles. Leaf spines never branch out but often grow in clusters at stem nodes. Most cacti and acacia plants have leaf spines.
skin spines are different from branch spines and leaf spines; they are the outward projections of the plant's cortex and epidermis and do not contain vascular tissue. Skin spines are found not only on stems but also on bark, leaves, and fruits.
The content mentioned above about plants with thorny stems and the defense mechanisms of plant stems—spines is hoped to be helpful to netizens!